能否举例说明怎样能看出宾语从句和定语从句

分别宾语从句和定语从句，可以看从句完整性。宾语从句是完整的结构，定语从句因为修饰名词，所以从句缺少其所修饰的名词，是不完整的结构。

例：He told the boy (that) somebody did him a favor. （从句结构完整，是宾语从句。）

He talked with the boy (who) did him a favor. (从句缺少the boy 作主语，是定语从句。）

He asked his teacher when they would have a meeting. （从句结构完整，是宾语从句）

He told his teacher the time when they would have a meeting. （从句缺少the time作状语，是定语从句。）

宾语从句和定语从句在位置上也有区别。

宾语从句=宾语，即动作（谓语）的承受者，只有“主+谓+宾”结构中才会出现宾语从句。在这种结构中，从句前为动词（必须是及物动词）。

例： He said (that) Jack would come here.

He asked when Jack would come here.

然而，“主+谓+宾”还可以延伸出“主+谓+直宾+间宾”结构。在这个结构中，人（sb.）作直接宾语，宾语从句作间接宾语，所以动词（必须是及物动词）和宾语从句中间出现直接宾语，也就是人称代词宾格或人名或表示人的名词。

例： He told me (that) Jack would come here.

He asked Mary when Jack would come here.

He asked the teacher when Jack would come here.

定语从句=定语，修饰名词，所以定语从句前必须有一个被定语从句修饰的名词，这个名词被称作“先行词”。名词作主语、宾语等不同成分时所处位置不同；因此，紧随先行词后的定语从句看起来位置不固定，其实，它只有一个位置：先行词后。

如，先行词作主语：

The person (that/who) told me the truth is standing in the crowd.

如，先行词做宾语：

I don't know the person (that/who) told me the truth.